Iron Sentinel
This page relates to a Metal Slug Attack unit; for information about this boss in the main series, see Iron Sentinel. The Iron Sentinel a playable unit in Metal Slug Attack. It serves as something of a "trophy unit", and is one of the few to have received continuous improvements to its base stats over the lifetime of the game. Parts are only available for purchase via the Mars Shop. The Sentinel itself is a very large multi-treaded tank that shoots missiles and projectiles from its ball turret. 3''' grants it a protective barrier which reduces all incoming attacks. If '''4 is unlocked, when first destroyed, it will switch to a secondary form that shoots even larger missiles with a wide area of effect and an increased damage output. This form possesses stun immunity, and the missiles fired cannot be nullified by enemy shields. Attacks Long Range Missile (Spread) - Launches a salvo of missiles from its side. If in second form, shoots out very large missiles. Special Big Missile (Spread) - Fires larger missiles from its main turret, and bombs from its side. Stats Items The Iron Sentinel uses a selection of unique items unavailable to any other units. Like the parts for the Sentinel itself, these can only be obtained via the Mars Shop (or fused using other items from the same). * Value shown in-game may differ, this is the actual effect. Skills Purchase Cost In order to obtain parts for the Iron Sentinel, surplus parts from platinum-framed units must be traded in at the Mars Shop: *1x Unit Parts (Normal) grants 1. *1x Unit Parts (Rare) grants 10. *1x Unit Parts (Super Rare) grants 40. 1,000 points are required per Sentinel part. Hence 80,000 points are required for Silver, another 100,000 for Gold, and another 150,000 for Platinum - 330,000 points in all. Since Mars Shop items are also required to equip the Sentinel, further points are required to fill out its skill slots: 900 for the first, 5,600 for the second, 65,000 for the third, 150,000 for the fourth, and a whopping 900,000 for the fifth - 1,121,500 in all. 1,451,500 Mars Points are hence required to fully evolve and equip an Iron Sentinel. On the other hand, a Silver Sentinel with only the first four skill panels unlocked costs a relatively low 301,500 points. The Task Force Extra Ops provides large amounts of unit parts, making it the easiest way to equip and evolve a Sentinel. All other options fall short by a large margin, although the MSP crank is the most viable runner-up, asking an average rate of around 2,000,000 MSP for 1,000 Mars Points (while also providing plenty of fusible items). Trivia *The Iron Sentinel is instead referred to as the "Iron Slider" within Metal Slug Attack's code. Its sprite sheet portrays the original Slider from Metal Slug 6, angled downhill - the game rotates its images to a levelled orientation at run-time. *The Iron Sentinel was buffed as of the 2.13.0 update, following player complaints about how weak it was for the time it took to use it properly. *The Iron Sentinel was further buffed again as of the 3.9.0 update. *The Iron Sentinel was further buffed again as well as a barrier skill replacing the critical, along with the second form being stun immune and its large missile being treated as a full-pierce projectile as of the 4.11.0 update.